Codechange: Use locals for company/deity mode during loops.

[PeterN]

Motivation / Problem

Script methods that build lists with ownership checks call ScriptObject::GetCompany() and/or ScriptCopmanyMode::IsDeity() for every iteration.

While individually these are not very expensive, the cost adds up.

Description

Instead, store the value of these calls in local variables before iterating the loops. This gives a reasonable benefit with large games and heavy scripts, though of course in practice results vary.

This is the result using Xarick's corona gs save from #10548:

Limitations

This is related to but conflicts with #11676. I'm made this a separate PR as it has wider scope and the changes are a bit more straightforward.

Checklist for review

Some things are not automated, and forgotten often. This list is a reminder for the reviewers.

• The bug fix is important enough to be backported? (label: 'backport requested')
• This PR touches english.txt or translations? Check the guidelines
• This PR affects the save game format? (label 'savegame upgrade')
• This PR affects the GS/AI API? (label 'needs review: Script API')
  • ai_changelog.hpp, game_changelog.hpp need updating.
  • The compatibility wrappers (compat_*.nut) need updating.
• This PR affects the NewGRF API? (label 'needs review: NewGRF')
  • newgrf_debug_data.h may need updating.
  • PR must be added to API tracker

[glx22]

As it already conflicts with the other PR, maybe switch to if (!...) continue where it reduces indentation.